1. If you have the time and think you can make a pro website you should do it.
2. If you think the time you have would invest somewhere else like promoting the site you should go for someone to do the job for you but remember don't go for cheap solution as that will not help in the long run.

One option is to use a simple CMS to create it. Many CMSs are complicated and need some time and coding skills before you can get something up, but some are simple and straightforward, and you just need to tweak a few settings. If you need anything changed in the code, you can hire a freelance PHP programmer to make the edits for you, which would cost significantly less than having someone build the site from scratch for you. The best simple CMS in my opinion is Website Baker. I had a site up and running in under an hour.

If you are marketing will primarily be online then you'll need SEO to optimize the site for search engines. You can learn SEO or hire someone to do it for you. If you decide to build for yourself then forums like this are a great place to get guidance and help as you go.

So there are many parameters to deciding whether to hire or to do it yourself. As for your question on scams, yes there are scammers everywhere in every profession. So you need to find someone who at least has a client base and you can get testimonials.